Material handling machine



May 14, 1957 D. M. SCHWARTZ MATERIAL HANDLING MACHINE 9 Sheets-Sheet lFiled June 15(1955 D. M. SCHWARTZ MATERIAL HANDLING MACHINE May 14, 1957Filed June 15, 195:

9 Sheets-Sheet 2 May 14, 1957 D. M. SCHWARTZ MATERIAL HANDLING MACHINE 9Sheets-Sheet 3 Filed June 15, 1955 May 14, 1957 D.- M. SCHWARTZ MATERIALHANDLING MACHINE 9 Sheets-Sheet 4 mm g elf Filed June 15; 1953 INVENTOIipW'J/f 1n. WW4

ATTORNEY May 14, 1957 Filed June 15, 1953 D. M. SCHWARTZ May 14, 1957 D.M. SCHWARTZ MATERIAL HANDLING MACHINE Filed June 15, 1953 9 Sheets-Sheet6 INVENTOR PM 721. 464900 5 BY A/ W ATTORNEY y 1957 D. M. SCHWARTZMATERIAL HANDLING MACHINE 9 Sheets-Sheet 7 Filed June 15, 1953 INVENTORFUQ BY HM M ATTORNEY May 14, 1957 D. M. SCHWARTZ MATERIAL HANDLINGMACHINE v 9 Sheets-Sheet 8 Filed June 15, 1953 INVENTOl 2M6 m M ATTORNEYMay 14, 1957 D. M. SCHWARTZ MATERIAL HANDLING MACHINE 9 Sheets-Sheet 9Filed June 15, 1953 I IN V EN TOR. M

MATERIAL HANDLING MACIWE Daniel M. Schwartz, Salt Lake City, Utah,assignor to The Eimco Corporation, Salt Lake City, Utah, a cor porationof Utah Application June 15, 1953, Serial No. 361,6tl1 6 Claims. ((11.214-148) This invention relates to an improved material handling machineof the front end bucket type and in particular to an improved materialhandling machine having an overhead bucket device supported on a mainframe which main frame is pivotally mounted on individually operatedcrawlers or self-laying track units.

It is an object of the invention to provide animproved device of thetype described wherein the material handling bucket device, the mainframe and the crawler units are constructed to permit pivotal suspensionof the main frame and its attached front end bucket device on individualcrawler units; to provide means whereby the digging load is transmitteddirectly to the main frame and then distributed evenly on the trackframes; to provide means whereby side digging loads are transmitteddirectly to the main frame thereby substantially reducing excessivestresses on the crawler diagonal brace and on the cantilever forwardextension of the track frame; to provide means whereby the weight of themain frame and the crawler units are effective to reduce the tendency ofthe material handling machine from overturning during the dischargecycle when provided with an overhead bucket mechanism; to provide meansfor readily varying the discharge distance and the overall height of theloader without interfering with the novel suspension system of theimproved machine; to provide such a machine having improved operatorvisibility and to provide a loader that is sturdy in construction andadaptable to many and varied working conditions.

These and other objects and advantages of the invention will appear moreclearly from the detailed description in connection with theillustrative embodimentsof the invention shown in the accompanyingdrawings in which:

Fig. 1 is a right front perspective view of the overhead materialhandling machine of the invention;

Fig. 2 is a right front perspective view of the loader shown in Fig. 1with the motor, cab and transmission covers removed;

Fig. 3 is a bottom plan view of the loader shown in Figs. 1 and 2 inpartial section and with the crawler treads and suspension wheelsremoved to more clearly show the crawler units;

Fig. 4 is a section on line 4-4 of the machine shown in Fig. 3;

Fig. 5 is a rear elevational view in partial section of the loader ofthe invention;

Fig. 6 is a fragmentary sectional view through the right rear tractorhousing;

Fig. 7 is a fragmentary sectional view on line 7-7 of Fig. 5;

Fig. 8 is an enlarged fragmentary section on line 88 of Fig. 4;

Fig. 9 is a top plan view of the equalizer bar shown in Fig. 8;

Fig. 10 is an enlarged detail top plan view of one of the equalizer barend bearings;

Fig. 11 is a side elevation of the bearing shown in Fig. 10; and

nited States Patent 0 i Patented May 14, 1957 Fig. 12 is a diagrammaticView of the lower portion of the device of the invention showing typicalloading of the main frame and equalizer bar.

With particular reference to Figs. 1, 2, 4 and 5 of the drawings, thereis shown a material handling apparatus embodying the principles of theinvention which generally comprises a main frame or body 10 pivotallymounted on individually operated crawler or self-laying track units 12and 14, as to be more fully described hereinafter.

The main frame 10 supports an overhead bucket assembly 16 upon paralleltracks or rails 18 secured to the main frame 10.

Each of the tracks 18 is provided with three support bracket membersgenerally designated 20, 22 and 24. Each of the bracket members startingwith the forward one 20 are stepped upwardly and rearwardly so the rails18 slope upwardly from the forward ends.

The overhead bucket structure 16 of the material handling machine is ofthe overhead rocker type. The side frames 26 of the rocker structurehave curved surfaces for rolling engagement with the parallel rails 18,the radius of curvature of the surfaces generally increasing from theforward to the rear ends of the curved sections. The curved surfaceshave inboard and outboard grooves to receive guide cables Which areconnected in reverse manner to the rocker structure and the main frame,as more fully described in my copending application Serial No. 346,402filed April 2, 1953 and now Patent No. 2,752,053.

Between the lower ends of the curved rocker arms is supported a shovelbucket 28 and each arm is also provided with a bumper 30 having a springloaded piston 32.

Flat cable chains 34 are attached at one end to the rocker arms justabove the bumpers Sil While the other ends are secured to bucket reels36, Rotation of the reels 36 raises the bucket from its forward lowdigging position to an upper and rearward discharge position.

In the dumping position the heads of the pistons 32 contact bumperplates 38 rigidly secured to a bumper frame 40. The bumper frame 40 andthe diagonal braces 42 are pin-connected at their ends to provide aneasily dismantled assembly that may be removed speedily when it isdesired to use the machine without the overhead rocker structure.

The overall height of the material handling machine and the dischargedistance of the loader is determined to a great extent by the height ofthe track members 18 at the rearward ends. The minimum height of therails is determined by the upper surface of the rear drive transmissionhousing generally designated 44, see Figs. 4 and 5.

The rails 18 as shown in full lines in the drawings rest just above thetop of the housing 44. However, where head room is not a criticalfactor, as it is in many mining operations, and greater dischargedistance is desired, the bracket members 22 and 24 are lengthened andthe angle of forward bracket 20 is slightly varied so that the rails maybe positioned as shown in broken lines in Fig. 4 of the drawings.

With the raised rails the curved surfaces of the rocker arms of theoverhead bucket mechanism would be modified so that correct alignment ofthe bracket reels 36 and the bumper frame 40 is maintained. However, theidentical rocker arms may be used with both the low and high rails bymerely modifying the bumper frame 40 and its bucket reels 36.

Thus it is seen that without affecting the drive mechanism of thetractor suspension system (as to be explained hereinafter) the heightand the discharge distance of the loader may be varied within Widelimits.

It will also be apparent that with the overhead bucket structure carriedby the main frame the digging load is transmitted directly to the mainframe and then distributed evenly on the track frames. In this form ofconstruction the side digging loads are also taken directly on the mainframe. Thus severe loads which have in the past been carried by therelatively light track frames are substantially eliminated.

In the center of the main frame is the power plant generally designated46 wherein is housed a prime mover to supply power for the shovel bucketand the self-laying tracks through transmissions 48 and 50 positionedforwardly and rearwardly of the prime mover.

A control cab 52 is positioned on the center line of the main framebetween the prime mover and the forward transmission 50 with theoperators seat 54, shown in its correct location in Figs. 2 and 4 of thedrawings, facing forwardly whereby the operator may observe the diggingand crowning of the bucket. The control cab 52 is provided with a sheetsteel top and metal grill work on four sides to provide visibility andprotection for the operator. The forward housing section 56 of themachine slopes generally downwardly to provide a clear line of visionfor the operator over the front end of the machine and the upper edge 58of the shovel bucket in its forward position. Thus the operator is ableto have an unobstructed view at all times of the material to beexcavated.

When the machine is used with an overhead bucket mechanism the top ofthe cab and the front housing 56 are shaped to clear the path of thebucket as it travels to the rear.

The endless track units 12 and 14 generally include track or swingframes connected to the material handling machine adjacent the rear end,and which are also pivotally connected to a transverse equalizer bar 62adjacent the front end of the machine.

With particular reference to Figs. 2, 3 and 7, each of the track framescomprises a pair of spaced side channel members 64 and 66 connectedtogether by transverse rib members 68 and a top plate 70. The top plates70 are notched at the front and rear ends to provide clearance for thefront idler wheels 72 and the sprocket wheels 74, respectively.

The outer side channel members 64 are of greater length than thecorresponding inner channel members 66.

ecured to these rearward extensions of the outboard channel members areself-aligning roller bearing units 76. The inner hearing race of theunits are carried by the live axle shafts 78 of each drive unit.

Each axle 78, as more clearly shown in Fig. 6, is journalled to the reartractor housing 44 by means of inboard and outboard bearings 80 and 82.Also secured to each axle is the sprocket wheel 74 and gear 84. The axleand sprocket wheel are driven through pinion 86 and gears 88 and 90 onthe intermerdiate shaft 92.

Each track frame unit is provided with a generally rearwardly extendingdiagonal brace member 94. The forward and large ends of the braces 9, 4are secured, preferably by welding to the inner track channel members66, forwardly of the bearing members 76 on the complementary outerchannel members.

The rearward ends of the diagonal braces 94 are each pivotally connectedto the main frame of the loading machine so that the track units arefree to pivot about the main frame with the outboard ends of live axles78 forming one of the pivot points and bearing 96, on center with theaxles 78, forming the other pivot point. Thus while the track frames arefree to pivot they are effectively prevented from toeing in or out andagainst lateral tilting relative to the main frame 10.

The bearing 96 generally comprises, as more clearly shown in Figs. 3 and5, a pivot pin 71 which is supported at its ends by clamping brackets 98and by inner clamping bracket 100. The space provided betweencorresponding pairs of inner and outer brackets are slightly greaterthan the width of the diagonal braces at their 4 rearward ends toprovide normal bearing clearance therebetween.

Each of the brackets 98 and 100 are of the conventional sleeve typehaving only one side split and are bolted to the under side of thehousing 44 by bolts 102. The brackets are also provided with centeringpins 104. The equalizer bar 62 and its connections with the main frameand each track frame will be described with particular reference toFigs. 3 and 8 through 11. The equalizer bar has four primary functions:firstly, the weight of the forward end of the main frame and itsattached structures is transmitted to the ground engaging crawler unitsthrough the bar; secondly, it transmits the substantial downward diggingforce from the main. frame to the track frames; thirdly, it permitsrelative pivotal movement between the crawler units and the main frame;and fourthly, provides the means whereby the weight of the main frameand the weight of the crawler units are all effective to reduce thetendency of the loader to overturn during the discharge cycle of theoverhead bucket mechanism. These four functions of the equalizer barwill become apparent from the following detailed description.

The equalizer bar 62 may comprise a rigid cast or forged steel memberhaving, in vertical section, a substantially straight center section106, upwardly curved intermediate portions 108, and substantially flatend portion 110, the outer extremities of which have circular crosssections.

The bar or member 62 may also be constructed of spring steel, orfabricated from a plurality of spring leaves. The advantages of thisform of construction would be additional cushioning of the load toabsorb strains on the main and crawler frames.

Centerly positioned on the bar are upstanding bosses 112 and 112' whichare bored as at 114 and 114' to receive a pivot pin 116. The inner andouter ends of the pivot pin 116 are secured in brackets 118 connected tothe center of the bottom of the main frame 10.

Thus the bar is free to pivot relative to the main frame 10 about thepin 116.

The outer circular ends of the bar are pivotally and slidably secured insubstantially universal bearings generally designated 120 which bearingsare fastened to their respective track frames by plates 122. In thepreferred form of the invention, with the material handling machine onlevel ground, the curvature of the bar and the height of the bosses 112and 112' are so selected that the pivotal axis of the bar with respectto the main frame and the pivotal axis of the ends of the bar and theircorresponding track frames are on a straight line.

With this straight line arrangement of the equalizer bar and its endpivots, pivotal movement of the bar provides the minimum amount ofsliding movement at the end bearings 120 and provides sliding movementin the same direction for movement of the bar above or below thecenterline.

Each of the end bearings 120 are identical and only one will bedescribed with reference to Figs. 10 and 11. The plate 122 is bolted bybolts 124 and 126 to the channel members and the top plate of thecrawler units, respectively. At the forward end of the plate is flangeor boss 128 bored to receive one end of a trunnion bearing 130. At therearward end of the plate a second flange or boss 132 is provided towhich is bolted a cover plate 134 carrying a second bearing 136 for theother end of trunnion bearing 130.

The center portion 138 of the trunnion bearing is radially bored as at140 to receive the circular end of the equalizer bar. The width of thecenter portion 138 of the trunnion bearing 130, and the distance betweenthe boss 128, and the boss 132 and its bearing 136 are so selected thatthere is provided limited axial sliding movement for the trunnionbearing 130 in addition to its normal pivotal movement. The spaceprovided for this sliding movement is designated A in Figs. 10 and 11.

In the preferred form of the invention the equalizer bar is positionedat the forward end of the main and track frames, for example, as shownin the drawings, the trunnion bearing supports are located justrearwardly of the front idler U-frame generally designated 73 (Fig. 3).

The importance of the forward position of the equalizer bar will beapparent from the following description of Fig. 12 which shows typicalloading factors of a machine constructed in accordance with theteachings of this invention. On overhead loading machines wherein thedistance B between the front and rear bearings is 95 inches and thedistance between the front idler bearing and the tip of the bucket inthe loading position C is 64 inches, it has been found that thefollowing forces are applied to the crawler frames when a digging loadof 20,000 pounds is applied at D:

1. portion of body weight at E 3,500 pounds;

2. portion of body weight vertically above the preferred position of theequalizer member F 5,500 pounds;

3. additional force at F due to digging load where distance G is 22%inches, 20,000 l59/72V2 or 43,000

pounds.

If the equalizer member is moved rearwardly to point P where thedistance H between F and F is 29 /2 inches, the force on the equalizermember due to digging load would then become 20,000 159/43 or 74,000pounds.

Thus it can readily be seen that the further forward the equalizermember is placed the less will be the total load on the equalizer memberand between the equalizer member and the main frame and crawler frames.

In operation of the suspension system of the invention as the materialhandling machine traverses uneven ground, the individual crawler unitsare free to pivot vertically with respect to the main frame. The pivotalaxis, as hereinbefore described, is the axis of the live axles 78. Asthe crawler units pivot up or down, the equalizer bar at its centerconnection also pivots about the pivot pin 116, and the followingmotions take place between the end of equalizer bar shown in the lefthand or high side of Fig. 8: the distance between the center of trunnionbearing 130 and the center of the equalizer bar increases and the end ofthe equalizer bar withdraws slightly from the bore 140 of the trunnionbearing 130; the angular relationship between the crawler units and theequalizer bar changes and the end of the equalizer bar rotates in thebore 140 while the trunnion bearing 130 rotates in the bearings 128 and136; and the trunnion bearing 130 shifts slightly laterally relative tothe bearings 128 and 136.

It will be seen that while the bearings 120 permit substantiallyuniversal movement between the equalizer bar and the crawler units, themain frame and the crawler units are still effectively interconnectedwhereby the weight of the main frame is equally distributed to thecrawler units, and the weight of the crawler units are always eflectiveto reduce the overturning effect of the high discharge momentum of theoverhead bucket mechanism.

While only the one form of connection between the equalizer bar and thecrawler units is specifically shown in the application drawings, it isapparent that other forms of bearing means could be satisfactorilyemployed without depending from the scope of the present invention. Forexample, a ball and socket connection could be employed wherein thesocket members are carried in self-centering spring urged bearing blocksattached to each of the crawler units.

It is further evident that while the particular application of themachine of the invention has been described with reference to a loaderhaving paired endless crawlers and an overhead bucket device, such meanscould be modified without substantially affecting the advantages of theinvention as described.

For example, the overhead bucket mechanism 16 could be replaced by astandard front end loading device Wherein the bucket is loaded, elevatedand discharged at the forward end. It is also apparent that the pairedcrawler units could be replaced by wheels supported at the forward endof the machine by means connected to the trunnion bearings 120, and thatthe machine would have substantial advantages even when employed withouta front end loading mechanism.

I claim:

1. A material handling machine comprising a main frame, an overheadrocker bucket device mounted for rolling engagement on said main framefrom a depressed forward digging position to an elevated rearwarddischarge position, paired lateral crawler frames, means mounting eachof said crawler frames from spaced transverse pivot points at therearward end of said main frame, a transverse equalizer member mountedfor transverse up and down pivotal movement with respect to said mainframe, the outer ends of said member being circular in cross section, asleeve bearing engaging the circular ends of the said member,cylindrical bearing surfaces extending at right angles to the bore insaid sleeve bearing, bearing blocks secured to the crawler frames andengaging the cylindrical bearing surfaces of said sleeve bearing, thedistance between said bearing blocks being so selected as to providelimited sliding movement of the cylindrical bearing surfaces in saidbearing blocks.

2. In a crawler tractor having a main frame and paired lateral trackframes pivotally mounted at the rearward end of the main frame; atransverse equalizer member pivotally mounted at the forward end of saidmain frame, and means universally mounting the ends of the equalizermember to said track frames comprising a trunnion bearing mounted oneach of the track frames for transverse pivotal movement with respect tothe main frame and sliding movement longitudinal with respect to themain frame, and bearing means mounting the ends of the equalizer memberin said trunnion bearing for substantially transverse sliding movementand lateral pivotal movement with respect to said main frame.

3. In a crawler tractor having a main frame and paired lateral crawlerframes pivotally mounted at the rearward end of the main frame; atransverse equalizer member mounted for transverse up and down pivotalmovement with respect to said main frame, the outer ends of said memberbeing circular in cross section, a sleeve bearing engaging the circularends of the said member, cylindrical bearing surfaces extending at rightangles to the bore in said sleeve bearing, and bearing blocks secured tothe crawler frames and engaging the cylindrical bearing surfaces of saidsleeve bearing, the distance between said bearing blocks being soselected as to provide limited sliding movement of the cylindricalbearing surfaces in said bearing blocks.

4. A material handling machine comprising a main frame, paired groundengaging wheels mounted at the rearward end of the main frame, atransverse equalizer member pivotally mounted at the forward end of saidmain frame, and means universally mounting the ends of the equalizermember to paired ground engaging wheels mounted at the forward end ofsaid main frame comprising a trunnion bearing mounted on each of theforward ground engaging wheels for transverse pivotal movement withrespect to the main frame and sliding movement longitudinal with respectto the main frame, and bearing means mounting the ends of the equalizermember in said trunnion bearing for substantially transverse slidingmovement with respect to said main frame.

5. A material handling machine comprising a body portion, an overheadrocker bucket device comprising paired rocker arms mounted for rollingengagement on said body portion, a stub axle journalled in each side ofthe body portion at its rearward end, paired lateral crawler frameshaving longitudinally extending spaced frame members, the outboard framemember extending in a rearwardly direction further than,the-.inboardmember, bearing means journalling said outboard framemembers to. the outboard: ends of said stub axles, inwardly andrearwardly extending diagonal brace rigidly secured to each of theinboard frame members, bearing means journalling the rearward extendingends of said. diagonal braces to the body portion, a transverseequalizer member pivotally mounted to the under side of said bodyportion at its forward end for limited up and down pivotal movement, theouter ends of said member being circular in cross section, a sleevebearing engaging the circular ends of the member, cylindrical bearingsurfaces extending at right angles to the bore in said sleeve bearing,bearing blocks secured to the crawler frames and engaging thecylindrical bearing surfaces of said sleeve bearing, the distancebetween said bearing blocks being so selected as to provide limited butpositive sliding movement of the cylindrical bearing surfaces in saidbearing blocks.

6. In a material handling vehicle including a body portion and pairedlateral crawler frames pivotally mounted at the rearward end of the bodyportion, a transverse oscillatory equalizer bar pivotally securedadjacent the forward end of the body portion with the ends of theReferences Cited in the file of this patent UNITED STATES IATENTS2,135,619 Johnston Nov. 8, 1938 2,233,627 McDonald Mar. 4, 19412,377,495 Hofmeister June 5, 1945 2,495,138 Royle Jan. 17, 19502,519,974 Mork Aug. 22, 1950 2,538,000 Hoar et al. Jan. 16, 19512,651,378 De La Liana Sept. 8, 1953 2,690,848 Beyerstedt Oct. 5, 19542,707,056 Gerst Apr. 26, 1955

